伴抗中性粒细胞胞质抗体的感染性心内膜炎患者临床特点分析

Clinical features of infective endocarditis with positive antineutrophil cytoplasmic antibodies

目的分析临床感染性心内膜炎(IE)抗中性粒细胞胞质抗体(ANCA)阳性和阴性患者的临床特点。方法对39例确诊为IE的患者,采用ELISA法检测血清ANCA,根据检测结果将患者分为ANCA阳性组和阴性组。回顾性分析患者的临床特点(一般情况、易感因素、临床表现、实验室检测指标和受累瓣膜等),并比较两组患者各项指标的差异。结果 39例IE患者中,13例ANCA阳性,阳性率达33.3%,均为PR3-ANCA阳性;26例为ANCA阴性患者。37例患者为自然瓣膜心内膜炎,其中34例有器质性心脏病,3例无基础心脏疾病。ANCA阳性组和阳性组间各种易感因素发生率比较,差异无统计学意义(P>0.05)。患者的主要临床表现包括贫血(66.7%)、脾脏肿大(38.5%)、肾病变(28.2%)、关节肿痛(23.1%)、下肢水肿(17.9%)等,其中ANCA阳性组患者下肢水肿发生率明显高于阴性组(38.5%vs 7.7%)(P<0.05)。实验室检测指标显示,所有患者出现C反应蛋白(CRP)水平升高现象,89.7%的患者红细胞沉降率(ESR)加快,66.7%的患者血红蛋白(Hb)水平下降,53.8%的患者出现蛋白尿,50.0%的患者出现血尿,但两组间各项指标比较差异无统计学意义(P>0.05)。37例患者进行了血培养,其中15例(40.5%)血培养阳性,ANCA阳性组血培养阳性率高于阴性组(69.2%vs 25.0%)(P<0.05)。共分离出17株致病菌,其中14株为链球菌。ANCA阳性组3例患者死亡,其中2例被误诊为ANCA相关小血管炎(AAV);阴性组无死亡病例。结论 ANCA在IE中有一定的阳性率,临床上将IE误诊为AAV存在一定的比例。因此,IE伴ANCA阳性的现象应引起临床高度重视。

Objective To investigate the clinical features of infective endocarditis （IE） with positive or negative antineutrophil cytoplasmic antibodies （ANCA）. Methods Thirty-nine patients with IE were were divided into ANCA positive group and ANCA negative group according to the serum ANCA findings by ELISA. The clinical features of patients such as general conditions, susceptible factors, clinical manifestations, laboratory indexes and involved valves were retrospectively analysed, and the parameters were compared between two groups. Results ANCA was positive in 13 of the 39 patients （33.3%）, and all were PR3-ANCA positive. Native valve endocarditis was diagnosed in 37 patients, and organic heart disease was present in 34 of them, while no basic heart disease was found in the other 3 patients. There was no significant difference in the prevalence of susceptible factors between ANCA-positive group and ANCA-negative group （P 〉 0.05）. The major clinical manifestations of patients included anemia 66.7%）, splenomegaly （38.5%）, nephropathy （28.2%）, arthralgia （23.1% ） and edema of lower extremity （ 17.9% The prevalence of edema of lower extremity in ANCA-positive group was significantly higher than that in ANCA-negatlve group （38.5% vs 7.7%） （P 〈 0.05）. As for .laboratory findings, higher C-reactive protein （CRP） values were found in all the patients, higher erythrocyte sedimentation rate （ESR） occurred in 89.7% patients, whilelower concentration of haemoglobin （Hb） was detected in 66.6% patients. Besides, 50.0% patients had hematuria, and 53.8% patients had proteinuria. However, there was no significant difference in all the laboratory indexes between two groups （P 〉 0.05）. Blood cuhures were performed in 37 patients, and a causative microorganism was identified in 15 （40. 5%） patients. The positive rate of blood culture in ANCA-positive group was significantly higher than that in ANCA-negative group （69.2% vs 25.0% ） （ P 〈 0.05）. Seventeen strains of pathogenic bacteria were isolated, among which 14 were Streptococcus. Three patients in ANCA-positive group died, among whom 2 were misdiagnosed as ANCA associated small vessel vasculitis （AAV）. There was no case of death in ANCA-negative group. Conclusion There may exist cases of ANCA-positive IE, which may be misdiagnosed as AAV. ANCA-positive IE may be attached great importance in clinics.